SYNAPTIC INTEGRATION AND DEVELOPMENT IN COMMAND NEURONS

命令神经元的突触整合和发育

• 批准号: 3412317
• 负责人: DONALD Hine EDWARDS
• 金额: $ 7.42万
• 依托单位: GEORGIA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 1991-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3412317
• 关键词: Malacostraca; animal developmental psychology; axon; biological models; biophysics; dendrites; electrical potential; electrophysiology; fresh water environment; ganglions; immature animal; interneurons; mature animal; mechanoreceptors; membrane structure; neuroanatomy; neurogenesis; neurons; stimulus /response; synapses

This research will investigate the mechanisms of synaptic integration in the lateral giant (LG) command neurons that trigger the escape tailflip of both developing and adult crayfish. Two questions will be addressed. The first asks how the LG's responses to mechanosensory inputs depend on the responses of tonic and phasic mechanosensory interneurons (MSIs) to tactile stimuli, the pattern of synaptic contact of individual MSIs on LG, the morphology of LG, and the passive and active membrane properties of LG. This question will be addressed by recording the responses of two identified MSIs, one phasic and one tonic, to mechanosensory stimuli that excite LG, by identifying possible MSI contact sites on LG and by recording LG's responses to them individually and in various patterns. The structural, biophysical and synaptic response data will be used to reconstruct the integrative properties of LG in a quantitative model that will acconut for the cell's responses to its normal patterns of input. The second question asks how the integrative properties of LG change during the animal's growth from post-natal fry to adult, and whether those changes and accompanying changes in synaptic inputs to LG can account for changes in tailflip behavior. We will analyse LG integrative properties in 2 cm, 6 cm and 12 cm animals in the manner described above, and develop quantitative models of them to determine how growth - related changes in cell shape, membrane properties and synaptic inputs should affect LG. We will also determine what changes occur in the number and pattern of inputs LG receives from identified MSIs and from the set of mechanosensory afferents. This study should identify the compensatory mechanisms that allow the labile disynaptic pathway to LG to remain viable during growth while the non- labile monosynaptic pathway fails. Since neuronal growth occurs in all nervous systems, both the changes in integrative properties during growth that we observe and the mechanisms that compensate for those changes may prove to be common features of developing nervous systems.

本研究将探讨突触的机制 整合到触发的侧巨（LG）命令神经元中 发育中和成年小龙虾的逃逸甩尾动作。 二 问题将得到解决。 首先询问LG的反应如何 对机械感觉输入的响应取决于强直和 触觉刺激的阶段性机械感觉中间神经元（MSI） LG 上单个 MSI 的突触接触模式， LG 的形态、被动膜和主动膜 LG 的特性。 这个问题将通过记录来解决 两种已识别的 MSI（一种是阶段性的，一种是强直性的）的反应 通过识别可能的机械感觉刺激来激发 LG LG 上的 MSI 联系网站并记录 LG 的回复 单独地和以各种模式。 结构、生物物理 和突触反应数据将用于重建 LG 在定量模型中的综合特性将 考虑细胞对其正常输入模式的反应。 第二个问题问LG的综合性能如何 动物从产后鱼苗到成体生长过程中的变化， 以及这些变化和伴随的突触变化是否 LG 的输入可以解释尾部翻转行为的变化。 我们将 分析LG 2cm、6cm、12cm综合性能 动物以上述方式，并开发定量 它们的模型来确定细胞中生长相关的变化如何 形状、膜特性和突触输入都会影响 LG。 我们还将确定数量和数量发生了什么变化 LG 从已识别的 MSI 和从 一组机械感觉传入。 这项研究应确定 允许不稳定的突触的补偿机制 LG 在增长过程中保持活力的途径，而非 不稳定的单突触通路失败。 由于神经元生长发生 在所有神经系统中，整合特性的变化 我们观察到的生长过程以及机制 补偿这些变化可能被证明是共同的特征 神经系统的发育。